Study on the environment effects on the tracers fadeaway in spraying deposite tests

Usually, tracers, instead of pesticides, were used in spraying experiments. The evaluation of the fadeaway of the tracers during the tests was significant for a reasonable explanation of the spraying performance. The fluorescent was used as tracers in the experiments involved in this research, in which the fadeaway rate of tracers was measured under different weather condition, shading rate, deposition carriers and sampling times. Fluorescein sodium was used for the fadeaway rate test and weather condition, shading rate, deposition carriers and sampling times were considered as constraints. Data analysis shown, it was significant interaction among sampling times, deposition carriers, shading rate and weather condition. The experiment shown, filter papers were more suitable as deposition carriers comparing to tinfoil papers and green sheet irons, sampling times were the best less than twenty minutes due to fluorescents were photodegradation. Cloudy days as weather condition had advantages over sunny days. The values of shading rate were essential for reasonable chosen owing to too high or too low values resulted in obvious difference of experiment results. On the condition of the same weather condition and shading rate, sampling time had an indispensable role on fadeaway rate of fluorescent tracers. The increase of sampling times would greatly raise the fadeaway rate of fluorescent tracers.